1. Field of Invention
This invention relates generally to a panel fastener or clip that normally fastens two panels together but allows for a predetermined displacement between the panels in response to a predetermined force applied to the panels.
2. Brief Description of the Related Art
In many applications the need arises to fasten one panel to another. For example, in the automotive industry the interior door panels of the vehicle must be securely fastened to the sheet metal forming part of the vehicle door. Many fasteners for this purpose have been proposed in the art. Examples of such panel fasteners can be seen in U.S. Pat. Nos. 5,758,987 and 6,042,296. However, there remains a need in the art for panel fasteners that, while securing two panels together under normal circumstances, will also allow for a controlled displacement between the two panels in response to the application of a predetermined force. An example, of an application requiring this type of fastener is in cars having side airbags that are concealed by the interior door panels. In such cars, when the side airbag inflates in an accident, the panels must be allowed to be displaced relative to one another to allow the airbag to be deployed properly, however, the panels should not be allowed to become completely disconnected. If an interior panel is allowed to separate completely upon deployment of the airbag, then the loose panel could act as a projectile that can cause injury to a vehicle's occupants. Furthermore, by limiting the displacement between the panels, reinstallation of the panel subsequent to the deployment of the airbag becomes much easier. The need persists in the art for a reliable and durable panel fastener or clip that will continue to tether two panels together while allowing for a controlled displacement between the two panels in response to a predetermined force.